<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>头尾固定中间高度自适应布局</title>
<style>
html, body {
    height:100%;
    margin:0;
    padding:0
}
#dHead {
    height:100px;
    background:#690;
    width:100%;
    position:absolute;
    z-index:5;
    top:0;
    text-align:center;line-height:100px;/*可删*/
}
#dBody {
    background:#FC0;
    width:100%;
    overflow:hidden;/*auto出现滚轮*/
    top:100px;bottom:100px;
    position:absolute;
    z-index:10;
    
}
.mycontent {
    padding:20px;
}
#dFoot {
    width:100%;height:100px;
    background:#690;
    position:absolute;
    z-index:200;
    bottom:0;
    text-align:center;line-height:100px;
}
</style>
</head>

<body>
<div id="dHead">固定头部100px</div>
<div id="dBody">
  <div class="mycontent"> 
  	中间自适应部分<br>
  	中间自适应部分<br>
  	中间自适应部分<br>
  </div>
</div>
<div id="dFoot">固定尾部100px</div>
</body>
</html>